Cthulu

TRUE Defense: Immunities are absolutely impossible to override, resistance is also impossible to override. On HT 2, Resistance becomes Immunity, on HT 3 Immunities reflect half damage back. On HT 4 Vulnerabilities are Normal. All attacks dealt with Cthulu are dealt with disadvantage, per HT, and on a hit, the dealer is dealt 10d20 worth of damage, per HT.

FULL REFLECTION 28/day: Any and all effects on Cthulu, he can choose to reflect onto anybody alive as a bonus action. Permanently.

HEALTH THRESHOLDS: Cthulu gains more power, and different abilities, every time his health goes down 1/4. HEALTH THRESHOLDS will be called HT.

INSANE: The Modifier for all his skills are +50

LEGENDARY RESISTANCE.78/day Cthulu can choose to succeed any Saving throw. 

LEGENDARY REGENERATION: Cthulu regains 150 HP per turn.

FINITE MAGICAL RESISTANCE: All spells of level 20 or below have no effect on Cthulu.

SLEEPING WHIM 32/day: Cthulu bends reality to his accordance. One of the following occurs when Cthulu takes damage.

• Cthulu absorbs half of it and reflects back the other half.
• Cthulu turns every point of damage into HP
• Cthulu creates 3 Hallows per HP point lost
• Cthulu creates 1 hallow per Damage point

Maddening Aura: Every character that ends their turn within 10 feet of Cthulu, has to attempt a DC 30 WIS check. On a fail, they are petrified, poisoned, and prone. Cthulu gains 1/12 of their current health per turn that they have any of those conditions. 

Spellcasting. Cthulu is a 100-level spellcaster. Its spellcasting ability is all Skills (spell save DC 60, +60 to hit with spell attacks). Cthulu has all spells prepared:
Cantrips (at will): ALL
ALL SPELLS (INFINITE slots):  

BREAK: Cthulu breaks all of the equipment that one player has, and that character has a -5 on all rolls for 1 minute. (The gear returns after 1 minute)

• For every HT, you can target another person with this, and you add another -5 to the subtraction. At HT 4 they fail all checks for 1d10 rounds. 

INTENSE GLARE: Everyone that can see Cthulu takes 9d20 damage every round for the rest of that session, if they fail a 20 DC no modifier SAVING THROW

• At HT 1 the target of the INTENSE GLARE Rolls a d8. An even number, the dice increases to 12d100 every turn they take for this session and the next. on an even number they instead become insane, and start killing everything around them, and cannot be killed unless they are grappled, or they take half their maximum HP worth of damage. Every HT increases there HP Maximum by 300, and gives them 400 HP immedietly, this extends into temporary HP. 

LAUNCH:Cthulu launches one of his eyes out of his body, up to 10,000 feet away, and can instantly do one of five things. Range and amount of targets increases by 12 per HT.

• Tentacles form out of the eye, grabbing up to 12 people and then pulling them to an area within 9,000 feet of him.
• Dozens of Hallows fall out of the eye, in dragon form
• A genormous beam of pure energy shoots out, dealing half of every character's health in the beams area, per turn that they end there. After two turns Cthulu can either pull his eye back or pull himself to his eye. If a player has not escaped the beam after two turns, they fall deafened and stunned for 6d4 rounds of combat.The beam is 805 feet wide, 900 feet tall and goes for 5000 feet forward.
• Cthulu traps everyoner infront of the eye in an illusion, where they are fighting an infinite amount of any creature the DM wants, on any terrain that th DM wants, and they do not escape until they die, every 6 seconds in the illusion world is 1d12 years in the real world. They still age and need food when in the illusion world, and they cannot come back unless they ALL die.

COIL. Melee Weapon Attack: +39 to hit, reach 30 ft., 3 target. Hit: 400 [ACID] damage.(THIS BREAKS THROUGH ALL IMMUNITIES AND RESISTANCE) 

REACH. Ranged Weapon Attack: +48 to hit, range 400/900 ft., 1 target. Hit: 200  [ACID] damage.(THIS BREAKS THROUGH ALL IMMUNITIES AND RESISTANCE)

PUSH: Ranged weapon Attack: AUTOMATIC HIT, 200/400 ft, 1 target. Hit: WHEN HIT BY THIS ATTACK, THE HIT CREATURE DOES TAKES 100 DAMAGE, and then Cthulu is healed 100x1D20 HP. The attacked creature rolls the D20 and applies all Modifiers to the roll.

HAS 2 BONUS ACTIONS + 2 PER HT

TURN: All damage dealt to Cthulu turns into hallows that will disappear in 6 rounds per, HT

ARE YOU, A GOD?: Cthulu uses this ability the first time that someone steps within ten feet of him. After the answer, Cthulu uses laugh three times.

LAUGH: Cthulu laughs, sending everyone within 300 feet of him per HT flying 30 feet per HT, landing prone.

Cthulu can only use this ability if he has HT 2

UN-LEASHED(Costs 2 Actions). Cthulu unleashes his pets, Godzilla, King Kong, and the abyssal dragon.  

DESTRUCTION(Costs 9 actions)Cthulu unleashes all of his tentacles. EVERYONE within a 600 feet radius must make a DC 39 DEX check, or be knocked prone for the next 3 minutes, and take 12d100 damage per turn that this active. This is active 5 minutes per HT.

EVERYONE:(costs 12 actions)Cthulu kills everyone alive once Per HT.

Cthulu can only use mythic when at 4 HT

NO (Costs 2 Actions). Cthulu rewinds time, giving himself all his power back, while his enemies stay at their current state.

STUPIDLY POWERFUL:(0 ACTIONS) CTHULU DOES 100000 DAMAGE PER LEVEL ON AN AUTOMATIC HIT TO EVERYONE IN A 1500 foot radius. FOR EVERY POINT OF DAMAGE THAT CTHULU DEALS, HE GAINS 1000000 HEALTH. IF HE KILLS 1000 LEVELS WORTH OF POWER THEN HE BECOMES TRUE CTHULU. True Cthulu has 999999999999999999999999 health and 1000000000000000000 ac, infinite range, and does 1000,000,000,000,000,000 damage. He immediately succeeds in all checks, and can only take damage if someone beats his ac. Every time someone roll's to hi6 against him is an automatic 1. Ac attacks stack between characters. Cthulu uses 100 attacks per turn. All are automatic hits. Be prepared to die.